Randolf Geist

Parallel Execution Skew – Skew Caused By Outer Joins

In the final part of this series I want to cover one last source of Parallel Execution Skew: Skew caused...

23 July 2014 6 min read

Randolf Geist

Parallel Execution Skew – Addressing Skew Using Manual Rewrites

In this part of the series we will have a look at different approaches to how Parallel Execution Skew can...

23 June 2014 13 min read

Randolf Geist

Parallel Execution Skew – 12c Hybrid Hash Distribution With Skew Detection

Since Parallel Execution Skew is a common problem that can severely limit the scalability of Parallel Execution (see my previous...

19 May 2014 9 min read

Randolf Geist

Parallel Execution Skew – Demonstrating Skew

After providing a baseline for Parallel Execution working as expected in the introduction of this series, in this part I’ll...

14 April 2014 8 min read

Randolf Geist

Parallel Execution Skew – Introduction

This is the first part of a mini-series about Parallel Execution Skew and how to address it. Introduction So what...

18 March 2014 10 min read

Randolf Geist

Analyzing and Troubleshooting Oracle Parallel Execution

Watch video The video above is accompanied by the following resources: Analysing and Troubleshooting Parallel Execution presentation slides (.pdf)...

17 April 2013 1 min read

Randolf Geist

HAVING Cardinality

When performing aggregate GROUP BY operations an additional filter on the aggregates can be applied using the HAVING clause. Usually aggregates are one of...

21 January 2013 2 min read

Randolf Geist

Oracle Cost-Based Optimizer Advanced

This video and set of resources is a follow up to the webinar broadcast by Red Gate on 01 August...

02 August 2012 2 min read

Randolf Geist

Incremental Partition Statistics Review

Here is a summary of the findings while evaluating Incremental Partition Statistics that have been introduced in Oracle 11g. The...

01 August 2012 2 min read

Randolf Geist

Dynamic Sampling (III) – Real-Life Data – Part II

In the previous installment of this series we saw that Dynamic Sampling wasn’t of great help when dealing with certain...

05 July 2012 11 min read

Randolf Geist

Dynamic Sampling (III) – Real-Life Data – Part I

In the previous parts of the series I outlined the basics on Dynamic Sampling. Let’s see how Dynamic Sampling deals...

20 June 2012 9 min read

Randolf Geist

Nested Loop Join Costing

The basic formula for calculating the costs of a Nested Loop Join is pretty straightforward and has been described and...

14 June 2012 2 min read

Randolf Geist

Oracle Cost-Based Optimizer Basics

This video and set of resources is a follow up to the webinar broadcast by Red Gate on 11 Apr...

10 April 2012 2 min read

Randolf Geist

Dynamic Sampling (I), an Introduction – Part 2

If you follow me on my blog you might wonder if I let you get away without an actual test...

08 February 2012 8 min read

Randolf Geist

Dynamic Sampling (I), an Introduction – Part 1

Welcome to my first post on AllThingsOracle.com! This is the initial part of a series highlighting different aspects of “Dynamic Sampling”....

30 January 2012 7 min read

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Randolf Geist

Randolf Geist's content

Parallel Execution Skew – Skew Caused By Outer Joins

Parallel Execution Skew – Addressing Skew Using Manual Rewrites

Parallel Execution Skew – 12c Hybrid Hash Distribution With Skew Detection

Parallel Execution Skew – Demonstrating Skew

Parallel Execution Skew – Introduction

Analyzing and Troubleshooting Oracle Parallel Execution

HAVING Cardinality

Oracle Cost-Based Optimizer Advanced

Incremental Partition Statistics Review

Dynamic Sampling (III) – Real-Life Data – Part II

Dynamic Sampling (III) – Real-Life Data – Part I

Nested Loop Join Costing

Oracle Cost-Based Optimizer Basics

Dynamic Sampling (I), an Introduction – Part 2

Dynamic Sampling (I), an Introduction – Part 1